1. Field of the Invention
The present invention relates to a method of manufacturing a module using a plurality of connection terminals that form an interlayer connection conductor, and also relates to a terminal assembly.
2. Description of the Related Art
As shown in an example module of the related art in FIG. 11, there has been known a module 500, in which various types of electronic components 502 are mounted on both surfaces of a wiring substrate 501, are sealed with resin layers 503 (for example, see Patent Document 1). Also, a metal shield layer 504 is provided on one principal surface of the module 500, and mounting terminals 505 for external connection are provided on the other principal surface. The metal shield layer 504 and the mounting terminals 505 are electrically connected with a wiring layer of the wiring substrate 501 through via conductors 506 for interlayer connection.
Each of the via conductors 506 is formed by forming a via hole in the corresponding resin layer 503 provided on the wiring substrate 501 by laser processing, applying desmearing to the via hole, and then filling the via hole with conductive paste containing, for example, Ag or Cu, or applying via fill plating to the via hole. If the via hole is formed in the resin layer 503 by laser processing as described above, the adjustment for the laser output may be troublesome, and hence the formation accuracy of the via hole may vary. Also, since the via conductors 506 are formed in the resin layer 503 through the plurality of steps, the manufacturing cost of the module may be increased, and the many steps may obstruct a decrease in the manufacturing time of the module. Also, a chemical solution used when desmearing is applied to the via holes formed in the resin layer 503 by laser processing or a chemical solution when via fill plating is applied to the via holes may erode the resin layer 503 and the wiring substrate 501.
Therefore, in recent years, as shown in FIG. 12, a terminal assembly 600, in which a plurality of columnar connection terminals 601 that form an interlayer connection conductor are integrally formed with a coupling body 602, is mounted on a wiring substrate 501 by a normal surface mount technology; and hence the interlayer connection conductor of a module is formed by the connection terminals 601 instead of the via conductors 506. Thus, attempts are made to decrease the manufacturing cost of the module and to decrease the manufacturing time of the module (for example, see Patent Document 2). That is, the adjustment for the laser output, or the processing using the chemical solutions, such as desmearing and plating, the processing which has been executed for formation of the via conductors 506 in the resin layer 503 through the plurality of steps including laser processing, is not required, and the module including the interlayer connection conductor can be manufactured by using a normal surface mount technology. FIG. 12 illustrates an example terminal assembly of related art.
Patent Document 1: International Publication No. 2005/078796 (Paragraphs [0017]-[0025], and [0035], FIG. 1, Abstract, etc.)
Patent Document 2: Japanese Unexamined Patent Application Publication No. 2008-16729 (Paragraphs [0015]-[0017], FIG. 4, etc.)